Magnus Bradbury came off the bench to replace Ritchie for the final 20 minutes at BT Murrayfield at the weekend and will also come into consideration.
Other back-row options in the squad include Sam Skinner, Nick Haining and the uncapped Andy Christie as head coach Gregor Townsend seeks the right blend alongside No 8 Matt Fagerson and openside flanker Hamish Watson.
Darge, also uncapped, plays at openside for Glasgow but Scotland forwards coach John Dalziel suggested a degree of flexibility may be required.
“Jamie when he first started was a seven,” said Dalziel. “That was the model we went for, having two sevens in the back row. It’s helped Jamie as he's developed as almost a hybrid player and is useful at the lineout.
“It’s a strength in Rory Darge’s armoury as well in terms of lineout, he gives us that option as well as he’s played a lot at eight. In terms of that skill-set he ticks a box as well, and that allows Hamish to play as well. We have a lot of different horses for courses and it’s about finding a blend to counter the threat that Wales will pose.
“Rory Darge has been in outstanding form. That’s the thing, in terms of players who are on form it’s so close. We’ve got options around there, Magnus Bradbury, options of others who can play at six. We’ll look at how to develop that on Tuesday, in terms of what we feel is the best blend to counter the threat Wales will pose.”
Josh Bayliss has also been ruled out. The Bath back-rower missed the England match with concussion and will sit out the game in Cardiff as well.
“It was one of those complex ones that had a little bit more symptoms, so we want to be careful with that,” said Dalziel.
“It’s been a couple of weeks and, with movement and travel when you’re dealing with that, it’s better just for Josh to stay where his medical team are.
“Hopefully he’ll be back to play some part in the Six Nations, possibly post Wales. We’ve got a week off and everything should be tidied up after that.”
The 20-17 win in the Calcutta Cup came despite England enjoying the lion’s share of possession and territory and Dalziel is looking for Scotland to do more with the ball in Cardiff on Saturday.
“I think we had 16 lineouts and six scrums, so we had enough [possession], maybe it’s just we didn’t use it well enough,” said the forwards coach. “There were a few errors here and there but I think that was the same for both teams.
"It was difficult conditions on the field with wet ball and the emotions of the game. But I think the amount of ball we had, it was just the use of it we’ll be looking to improve on this week.”